A new cost effective, long life and low resistance filter cartridge for water treatment

Filtration processes constitute the major solution among water treatments, which appear always necessary nowadays to make water suitable for human consumption or domestic uses, due to the gradual deterioration of its quality as a consequence of environmental pollution and industrial processes. In this paper a new type of filtering cartridge is presented, aimed at overcoming the main inconveniences shown by usual commercial cartridges. These drawbacks have been highlighted in a previous experimental work conducted in the Laboratory of Environmental and Maritime Hydraulics (LIDAM) of University of Salerno and aimed at evaluating the head losses produced by the most common filtration cartridges, especially under progressive clog conditions. Head losses, in fact, are particularly undesirable for low-pressure plants, where they can inhibit the normal operation of the installed apparatus. The analysis of the experimental results permitted to reveal several features of the filtration process in commercial cartridges and draw up different remarks, which led, after further laboratory tests here presented, to the design of a new economic, non-toxic, low-resistance and long life-cycle filtration cartridge, proposed and described in this paper. This cartridge, is basically made of a central element in inert cotton wrapped in a cylindrical polypropylene support, similar to the commercial one but with the core protected by elements, such as white marble pebbles, effective microorganism ceramic cylinders and granular active coal, which, while ensuring a good hydraulic permeability, is capable of stopping much of the particles suspended in the fluid before they reach the cartridge causing its clogging. The new design permits, therefore, to significantly reduce, compared with the commercial cartridges, average head losses even for high clogging degrees, and to increase, as a consequence, the life cycle of the cartridges.